cn0391.c File Reference

Implementation of CN0391 board support. More...

#include <stdlib.h>
#include "cn0391.h"
#include "no_os_thermocouple.h"
#include "no_os_rtd.h"
#include "no_os_alloc.h"
#include "no_os_error.h"
#include "no_os_print_log.h"

Include dependency graph for cn0391.c:

Functions
int	cn0391_init (struct cn0391_dev **dev, struct cn0391_init_param *init_param)
	Initialize CN0391 device: set up AD7124 and configure IOUT.
int	cn0391_remove (struct cn0391_dev *dev)
	Remove CN0391 device and free resources.
int	cn0391_read_temperature (struct cn0391_dev *dev, uint8_t ch_idx, double *hot_junction_temp, double *cold_junction_temp, double *thermocouple_voltage, double *rtd_resistance)
	Perform a full temperature measurement cycle. Reads all 3 ADC channels (thermocouple, reference resistor, CJC RTD), computes cold junction temperature, cold junction compensation voltage, and hot junction temperature.

Detailed Description

Implementation of CN0391 board support.

Author

Mircea Vlasin (mirce.nosp@m.a.vl.nosp@m.asin@.nosp@m.anal.nosp@m.og.co.nosp@m.m)

Copyright 2026(c) Analog Devices, Inc.

SPDX-License-Identifier: BSD-3-Clause

Function Documentation

cn0391_init()

int cn0391_init	(	struct cn0391_dev **	dev,
		struct cn0391_init_param *	init_param )

Initialize CN0391 device: set up AD7124 and configure IOUT.

Parameters

dev	- Pointer to pointer to CN0391 device descriptor.
init_param	- Initialization parameters.

Returns

0 on success, negative error code otherwise.

cn0391_read_temperature()

int cn0391_read_temperature	(	struct cn0391_dev *	dev,
		uint8_t	ch_idx,
		double *	hot_junction_temp,
		double *	cold_junction_temp,
		double *	thermocouple_voltage,
		double *	rtd_resistance )

Perform a full temperature measurement cycle. Reads all 3 ADC channels (thermocouple, reference resistor, CJC RTD), computes cold junction temperature, cold junction compensation voltage, and hot junction temperature.

Parameters

dev	- CN0391 device descriptor.
ch_idx	- IIO channel index (CN0391_CH0_ID..CN0391_CH3_ID).
hot_junction_temp	- Pointer to store hot junction temperature (°C).
cold_junction_temp	- Pointer to store cold junction temperature (°C).
thermocouple_voltage	- Pointer to store thermocouple voltage (mV).
rtd_resistance	- Pointer to store measured RTD resistance (Ohms).

Returns

0 on success, negative error code otherwise.

cn0391_remove()

int cn0391_remove

(

struct cn0391_dev *

dev

)

Remove CN0391 device and free resources.

Parameters

dev	- CN0391 device descriptor.

Returns

0 on success, negative error code otherwise.